The present invention relates to the field of conveying flat media, and particularly to the use of belt-type conveyors that capture mail items between opposed flexible belts to transport and direct mail items in processing operations.
Apparatus and systems utilizing opposed xe2x80x9cpinchedxe2x80x9d flexible belts for transporting and directing flat media such as currency, cards and similar items of generally uniform size are known. Such xe2x80x9cpinched belt pathxe2x80x9d devices create a path or course formed by opposing flexible belts traveling in the same direction wherein media is captured between the belts and carried along the path or course defined by the belts. In such systems it is often necessary to direct the media to (1) one of several selected diverging paths or (2) from one of a plurality of converging paths to a single path. In practice this is not a trivial task.
Transport devices using pinched belts to xe2x80x9ccapturexe2x80x9d both sides of transported media must keep the media captured between the belts at all times in order to avoid having the media change speed, jam or become skewed with respect to the belt path. However, in most, if not all, pinched belt applications the media must be temporarily released from between the belts at some time to accomplish certain functions. It may be necessary to temporarily release the media when the media must pass a vision or scanning system to enable reading of indicia from the media""s surface. Likewise, it may be necessary to combine multiple media streams into a single stream with a converging path device, or direct media along one of a number of different paths in a diverging path device. In these instances, the media must typically be transferred from one set of opposed or pinched belts to another.
Current methods of diverting media xe2x80x9ccapturedxe2x80x9d or pinched between opposing flexible belts typically involves the use of a knife-like gate that is moveable between two or more positions to divert media items along one of several selected paths. Such a device is described in U.S. Pat. No. 5,536,002 which discloses a conveyor for conveying paper sheets including a three way directional switching unit. The directional switching unit includes conveyor belts for conveying cash bills, sheet guides associated with the conveyor belts to guide the bills and a gate for directing the cash bills. The gate is formed in the shape of a triangle and mounted on a plate that moves in a circular fashion so as to move the gate through an eccentric path, thereby changing the path of bills moving through the unit.
To direct items from multiple paths to a single path, current methods typically rely on stationary sheet guides to direct media received from multiple conveyors, each comprising a pair of opposed belts forming a pinched belt path, to a single such conveyor. In each of these cases, prior art devices relinquish control, i.e., the media is released from between belts, for some distance or period. As noted above, releasing the media in this manner entails a risk that the media will skew, jam or both.
Thus, there is a need for an improved apparatus for directing media, such as mail items, paper sheets and the like along converging and/or diverging paths.
In one embodiment the invention comprises a pinched belt conveyor system for transporting flat media along converging or diverging paths. The system includes at least one fixed, vertically oriented belt and at least one moveable selector belt for transporting media therebetween. The moveable belt may be shifted between a first position wherein media received between the fixed belt and moveable belt is transported from one of a plurality of converging paths to a single path, or from a single path to one of a plurality of diverging paths and a second position where the moveable belt is positioned away from the fixed belt. The moveable belt is offset vertically from the fixed belt so that the moveable belt may pass above the fixed belt when moved horizontally from the first position to the second position. Alternatively, the moveable belt may be configured so as to move below the fixed belt when moved from the first position to the second position.
In one aspect the movable selector belt is mounted on a first, moveable frame while the fixed belt is mounted on a second fixed frame. In this aspect the moveable frame includes parallel bottom and top support members and a plurality of uprights configured to move in slots in the fixed base frame. A plurality of guide rollers are mounted on parallel support members opposite the selector belt and are vertically offset from the moveable belt. In operation, flat media items, such as mail pieces transported between the fixed belt and moveable belt are supported on a first side by the fixed belt and on the second side by the moveable belt and one or more guide rollers.
In another aspect the invention includes a conveyor apparatus having a first fixed frame including a plurality of fixed, vertically oriented flexible belts mounted thereon and a second moveable frame including a plurality of vertically oriented selector belts mounted thereon. The movable frame includes a pair of parallel supports between which the fixed frame is disposed. At least a first one of the moveable belts and a fixed belt transport media therebetween along a first path when the moveable frame is in a first position and at least a second one of the moveable belts and a fixed belt transport media therebetween along a second path when the moveable frame is in a second position. In this aspect, one of the movable belts passes through the first path when the moveable frame is moved from a first position to the second position. The apparatus can transport media from one of: (1) a first one of a plurality of converging paths to a single path, and (2) from a single path to a first one of a plurality of diverging paths when the moveable frame is in a first position depending upon the direction of travel of the belts. In a second position the apparatus can transport media between at least one of the fixed belts and at least one of the moveable belts from one of: (1) a second one of a plurality of converging paths to a single path, and (2) from the single path to a second one of the plurality of diverging paths, again, depending upon the direction in which the belts are traveling.
In another aspect, the invention comprises a conveyor system, including a first pair of fixed conveyor belts positioned to engage a flat item therebetween and transport the flat item along a main conveyor path, a second pair of fixed conveyor belts positioned to engage a flat item therebetween and transport the flat item along a first branch path and a third pair of fixed conveyor belts positioned to engage a flat item therebetween and transport the flat item along a second branch path. A first moveable belt can be positioned in alignment with one of the fixed belts to form a first divert path that transports the item from the main path to the first branch path and a second moveable belt can be positioned in alignment with a second one of the fixed belts to form a second divert path that transports the item from the main path to the second branch path. The first and second moveable belts are mounted on a common frame and move in tandem, such that moving the first moveable belt out of the first divert moves the second moveable belt into the second divert path. The first and second moveable belts are also laterally offset form the fixed belts, so that each movable belt can move into and out of the divert paths without interference with any of the fixed belts. During transport of a flat item, the movable and fixed belts engage opposite side portions of the flat item during movement of through the divert paths. In this aspect, the conveyor system includes a controller that receives signals indicating which branch path an item should be diverted to and means responsive to signals from the controller for moving the movable belts to form the first or second divert path as the item passes out of the main conveyor path into one of the divert paths.